Bendigo Mines Pumped Hydro Project

Background

Bendigo’s long history as a gold-mining town has left a legacy, which includes a significant amount of now unused underground mine workings. The Bendigo mining area consists of seven major mine reef workings with approximately 5,000 shafts, the majority of which are shallow, but with some over 500 m deep and a few over 1000 m deep and the deepest at 1,406 m.

Pumped Hydro Energy Storage

Pumped hydro energy storage (PHES) can store energy in some ways like a rechargeable battery. It operates similarly to a traditional hydropower system where water from a high elevation is channelled through a turbine to spin a generator and supply electricity, except that it can also pump water from a lower point to a higher point by consuming electricity. This means that while it is not itself a source of energy, it can be used as a tool to match energy supply with demand where direct control over the timing of generation is not possible, as is the case with renewable sources such as solar and wind energy. Pumped hydro energy storage is a mature technology, making up approximately 97% of gridscale energy storage globally.

Pumped Hydro for Bendigo

As part of a broader push to transition Bendigo to renewable power sources, the Bendigo Sustainability Group (BSG) proposed and investigated the possibility of a pumped hydro energy storage system in the mine workings. Over a 12 month period it then developed and then promoted the idea to the City of Greater Bendigo and DELWP for further investigation. $150,000 in funding was secured to undertake a pre-feasibility study which was completed in March 2018.

It is the Bendigo Sustainability Group’s intention that as much of the pumped hydro energy storage as possible ultimately be community owned by members and businesses from Bendigo and Central Victoria so that the financial benefits remain locally here.

Click here for a BSG summary document RePower Bendigo with Renewable Energy Generation and Pumped Hydro Energy Storage. This document is from March 2017 and was part of briefing information to the Minister for Energy, Environment and Climate Change, Lily D’Ambrosio as we were seeking funding for the pre-feasibility study.

Bendigo Mines Pumped Hydro Pre-Feasibility Study

After much research, concept development and lobbying by volunteers from the Bendigo Sustainability Group, we were successful in having the Victorian Government and City of Greater Bendigo co-funded a pre-feasibility study into renewable energy pumped hydro using existing mining infrastructure in and under Bendigo. The BSG provided the project concept and other resources, held a steering committee role and facilitated engagement with local stakeholders.

The study found that the project has the potential to be technically feasible and economically viable, and should progress to a full feasibility study.

The concept proposed for further development is an inter-reef pumped hydro system with a capacity of up to 30 MW which could store up to six hours, or 180 MWh, of energy. The project has the potential for a wide variety of benefits, including:

the ability to support deeper integration of renewable energy in the region;

a strong prospect for cost-effective energy storage in regional Victoria, which could help Bendigo achieve its goal of becoming a net exporter of renewable energy; and

the potential to develop a world-first underground pumped hydro project in regional Victoria.

The government is seeking expressions of interest from industry and other parties to progress this work into a full feasibility study. For more information and to access a full copy of the pre-feasibility study go to the link below:

Click here for a video of the proposed concept for the Bendigo Pumped Hydro Energy Storage.

Click here for information available on the consultant’s (ARUP) website.

The project is an exciting prospect for cost-effective energy storage in regional Victoria through adaptive reuse of existing infrastructure and a detailed feasibility study is the next step in the development of this project. A detailed feasibility study will provide sufficient site investigations and design development to respond to key technical risks. Procurement and tender activities for construction of the project and contracting of its power and ancillary services will enable a final investment decision on the project.

Powering Pumped Hydro Energy Storage

A Bendigo PHES would have to be powered by new small, medium and large scale renewable energy generation capacity to be built in and around Bendigo and throughout central Victoria. It is likely that a fair portion of this generation would be from solar PV due to our very good solar resources and relatively poor wind resource. The excess power generated from the solar during the day would be used to pump the water in the pumped hydro energy storage back up to higher levels within the mine workings. This same water would then be released back down to the lowed levels again driving turbines thus generating electricity when it is needed – which would predominantly be during the afternoon and early evening peaks in demand (3 to 9 p.m.) as well as some overnight.

For information on how the Bendigo Sustainability Group proposes to power Central Victoria and the pumped hydro energy storage with community owned renewable energy visit https://www.bsg.org.au/community-energy/